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<a name="Z80-Directives"></a>
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Next: <a href="Z80-Opcodes.html#Z80-Opcodes" accesskey="n" rel="next">Z80 Opcodes</a>, Previous: <a href="Z80-Floating-Point.html#Z80-Floating-Point" accesskey="p" rel="prev">Z80 Floating Point</a>, Up: <a href="Z80_002dDependent.html#Z80_002dDependent" accesskey="u" rel="up">Z80-Dependent</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="AS-Index.html#AS-Index" title="Index" rel="index">Index</a>]</p>
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<a name="Z80-Assembler-Directives"></a>
<h4 class="subsection">9.53.4 Z80 Assembler Directives</h4>

<p><code>as</code> for the Z80 supports some additional directives for
compatibility with other assemblers.
</p>
<a name="index-Z80_002donly-directives"></a>
<p>These are the additional directives in <code>as</code> for the Z80:
</p>
<dl compact="compact">
<dt><code>db <var>expression</var>|<var>string</var>[,<var>expression</var>|<var>string</var>...]</code></dt>
<dt><code>defb <var>expression</var>|<var>string</var>[,<var>expression</var>|<var>string</var>...]</code></dt>
<dd><p>For each <var>string</var> the characters are copied to the object file, for
each other <var>expression</var> the value is stored in one byte.
A warning is issued in case of an overflow.
</p>
</dd>
<dt><code>dw <var>expression</var>[,<var>expression</var>...]</code></dt>
<dt><code>defw <var>expression</var>[,<var>expression</var>...]</code></dt>
<dd><p>For each <var>expression</var> the value is stored in two bytes, ignoring
overflow.
</p>
</dd>
<dt><code>d24 <var>expression</var>[,<var>expression</var>...]</code></dt>
<dt><code>def24 <var>expression</var>[,<var>expression</var>...]</code></dt>
<dd><p>For each <var>expression</var> the value is stored in three bytes, ignoring
overflow.
</p>
</dd>
<dt><code>d32 <var>expression</var>[,<var>expression</var>...]</code></dt>
<dt><code>def32 <var>expression</var>[,<var>expression</var>...]</code></dt>
<dd><p>For each <var>expression</var> the value is stored in four bytes, ignoring
overflow.
</p>
</dd>
<dt><code>ds <var>count</var>[, <var>value</var>]</code></dt>
<dt><code>defs <var>count</var>[, <var>value</var>]</code></dt>
<dd><p>Fill <var>count</var> bytes in the object file with <var>value</var>, if
<var>value</var> is omitted it defaults to zero.
</p>
</dd>
<dt><code><var>symbol</var> equ <var>expression</var></code></dt>
<dt><code><var>symbol</var> defl <var>expression</var></code></dt>
<dd><p>These directives set the value of <var>symbol</var> to <var>expression</var>. If
<code>equ</code> is used, it is an error if <var>symbol</var> is already defined.
Symbols defined with <code>equ</code> are not protected from redefinition.
</p>
</dd>
<dt><code>set</code></dt>
<dd><p>This is a normal instruction on Z80, and not an assembler directive.
</p>
</dd>
<dt><code>psect <var>name</var></code></dt>
<dd><p>A synonym for See <a href="Section.html#Section">Section</a>, no second argument should be given.
</p>
</dd>
</dl>




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